Typical drapers of pick-ups for a combine include a plurality of side by side joined endless belts wrapped around front and rear parallel spaced rollers where one of the front and rear rollers is a driven roller to drive the belts to carry crop rearwardly from the front roller to the rear roller.
The draper belt arrangements of a combine pickup available on the market typically have tracking and slippage issues in that the belt arrangement must be guided to properly track around the front and rear rollers and must be driven in a manner which limits slippage of the belts on the driven roller. Tracking of drapers currently is done by guiding disks on the exterior surface of the rollers or in some cases by adjusting the position and/or tension of the outer roller supports. In such pick-ups the twisting of the deck as it moves across the ground combined with the short distance between the front and rear rollers causes the draper to wander laterally. At the same time there is a tendency for the belts to slip relative to the driven roller so that the feed rate changes in an unacceptable manner.
The slippage issue is determined to be a result of roller deflection due to the draper tension causing the middle draper belts to have less tension than the outer belts. Solutions to the deflection of these long rollers include having roller diameter which is larger in the center with respect to outer ends, changing one long roller into two shorter rollers or pusher devices to limit deflection of roller. All these solutions not only are not cost effective but have not adequately functionally performed.
In U.S. Pat. No. 6,131,728 (Rizhanovsky) issued Oct. 17, 2000 to Precision Metal shows an end to end connection for the ends of a draper suitable to be used on a pick-up of this type.
In U.S. Pat. No. 7,344,020 (Grywacheski) issued Mar. 18, 2008 to Deere shows another connection for a draper suitable to be used on a pick-up of this type.
Neither of these patents addresses the issues of slippage or guidance.